Is plasma and urine neutrophil gelatinase-associated lipocalin (NGAL) determination in donors and recipients predictive of renal function after kidney transplantation?

ObjectivesDelayed graft function (DGF) is still a major issue in kidney transplantation. Plasma and urine neutrophil gelatinase-associated lipocalin (NGAL) were evaluated in a population of kidney donors and recipients to investigate their performance to predict early renal function.Design and methodsPlasma (pNGAL) and urine (uNGAL) samples were obtained from donors before organ procurement, and from recipients before transplantation, and then 6, 24 and 48 h after the procedure. Kidney transplantations were performed from both living donors (LDs, n = 17) and deceased donors (DDs, n = 80). Recovery of renal function was evaluated as the time to reach serum creatinine < 2 mg/l or glomerular filtration rate (GFR) > 40 mL/min. Logistic regression was used to assess the ability of different variables to predict the occurrence of DGF.ResultsPlasma NGAL levels were significantly lower in LDs than in DDs. No episodes of DGF were recorded among LD kidney recipients, but DGF was observed in 25% of patients in the DD group. There was no correlation between donor pNGAL and uNGAL values and the occurrence of post-transplant DGF. Recipient pNGAL performed better than uNGAL in terms of predicting DGF occurrence. Donor pNGAL and uNGAL values did not influence the time needed to reach serum creatinine levels of < 2 mg/dl after transplantation. When time to reach eGFR of > 40 mL/min is considered, only donor uNGAL seems to be a predictor of graft function recovery. However, recipient pNGAL values obtained 24 and 48 h after transplantation, but not uNGAL values, were found to be a significant predictor of graft function recovery.ConclusionsPlasma NGAL level determination in recipients, but not in donors, proved to be a reliable predictor of DGF occurrence and renal function restoration, but too long for an interval to be able to compete with biomarkers currently used in clinical practice.